Biochemistry, Biophysics, and Structural Biology Commons^™

Involvement Of Post-Transcriptional Histone Modifications In Chromosome Missegregation, Jessica N. Gabbard, Ann Kirchmaier

The Summer Undergraduate Research Fellowship (SURF) Symposium

Proper chromosome segregation during mitosis ensures the equal inheritance of parental DNA by two daughter cells. Errors in chromosome segregation result in aneuploidy, the inheritance of abnormal chromosome numbers. Aneuploidy is a characteristic of tumors cells; therefore, understanding the factors that cause chromosome missegregation will provide insight into carcinogenesis. Certain post-transcriptional histone modifications in centromeric and pericentromeric regions are associated with maintaining kinetochore integrity and ensuring proper chromosome segregation. However, whether loss or improper distribution of modifications directly or indirectly causes chromosome missegregation is yet to be determined. To compare the DNA content of mutated yeast strains relative to WT, …

Examining The Link Between Chromosomal Instability And Aneuploidy In Human Cells, Sarah L. Thompson, Duane A. Compton

Dartmouth Scholarship

Solid tumors can be highly aneuploid and many display high rates of chromosome missegregation in a phenomenon called chromosomal instability (CIN). In principle, aneuploidy is the consequence of CIN, but the relationship between CIN and aneuploidy has not been clearly defined. In this study, we use live cell imaging and clonal cell analyses to evaluate the fidelity of chromosome segregation in chromosomally stable and unstable human cells. We show that improper microtubule–chromosome attachment (merotely) is a cause of chromosome missegregation in unstable cells and that increasing chromosome missegregation rates by elevating merotely during consecutive mitoses generates CIN in otherwise stable, …

Detection Of Aneuploidy For Chromosomes 7 And 8 Using Fluorescence In Situ Hybridization In Patients With Aplastic Anemia And Sequencing Of The Mitotic Checkpoint Gene Hbub1, Laura Jane Aridgides

Theses and Dissertations in Biomedical Sciences

Aplastic anemia (AA) is characterized by complete bone marrow failure. Progression to myelodysplastic syndromes (MDS) and acute nonlymphocytic leukemia (ANLL) occurs frequently. At the time of transformation, cytogenetic abnormalities are common. Detection of cytogenetic abnormalities prior to leukemic transformation may indicate future disease progression. Karyotype analysis is the current method of choice to evaluate chromosome aberrations. However, fluorescence in situ hybridization (FISH) is more sensitive in detecting these abnormalities.

hBUB1, a mitotic spindle checkpoint gene, was shown to be mutated in two colorectal cancer cell lines with high levels of aneuploidy (Cahill, et al., 1998). Although theoretically possible, conclusive …

Effects Of Chemical Aneuploidogens On Taxol Purified Drosophila And Mouse Brain Microtubules Polymerization And Depolymerization In Vitro, Anil Sehgal

Biological Sciences Theses & Dissertations

The effects of aneuploidogens (aneuploidy causing agents) on taxol-purified microtubules from Drosophila and mouse brain in vitro were studied by using a spectrophotometric assay and electron microscopy. Colchicine, acetonitrile, propionitrile, acrylonitrile, dimethyl sulfoxide (DMSO), griseofulvin and cadmium chloride inhibited microtubule polymerization whereas methoxyethyl acetate (MEA) and methyl mercuric chloride (MMC) did not. All aneuploidogens tested (at 50mM) resulted in reduced rate of elongation of mouse brain microtubules. MMC, cadmium chloride and DMSO resulted in increased rates of Drosophila microtubule elongation whereas the rest of the drugs resulted in decreases. The in vitro results from Drosophila correlate well with the previously …